等离子喷涂Cr3C2/NiCr金属陶瓷基高温润滑涂层的摩擦学行为研究  

Tribological Behavior of Plasma Sprayed Cr3C2/NiCr Cermet Based High Temperature Lubrication Coatings

作　　者：周琪 卢礼灿 易戈文[2] 王文珍[2] 贾均红[2] ZHOU Qi;LU Li-can;YI Ge-wen;WANG Wen-zhen;JIA Jun-hong(Schoolof Chemistry, Xiangtan University, Xiangtan 411100, China;State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China)

机构地区：[1]湘潭大学化学学院,湖南湘潭411100 [2]中国科学院兰州化学物理研究所固体润滑国家重点实验室,兰州730000

出　　处：《表面技术》2019年第8期212-217,共6页Surface Technology

基　　金：国家自然科学基金(51575505,51675508)~~

摘　　要：目的探讨和研究Cr3C2/NiCr-Ag-MoO3-CaF2和Cr3C2/NiCr-CaF2金属陶瓷涂层与ZrO2配副在宽温域(室温~800℃)内的摩擦磨损行为和磨损机理。方法以Cr3C2/NiCr作为基底材料,CaF2、Ag、MoO3作为固体润滑剂,采用大气等离子喷涂技术在718高温合金钢基体表面,制备Cr3C2/NiCr-Ag-MoO3-CaF2和Cr3C2/NiCr-CaF2金属陶瓷涂层。采用UMT-3高温摩擦磨损实验机评价涂层从室温~800℃的摩擦磨损性能,采用显微硬度计和万能材料实验机测试涂层的显微硬度和粘结强度,采用X射线衍射仪(XRD)、扫描电子显微镜(SEM)和拉曼光谱仪分析涂层的显微结构、物相组成和磨痕的微观形貌。结果Cr3C2/NiCr-CaF2和Cr3C2/NiCr-Ag-MoO3-CaF2金属陶瓷涂层结构致密,显微硬度和结合强度均随着固体润滑剂含量的增加而有所下降,结合强度分别为46.45、36.65MPa,显微硬度分别为524.61HV0.3、478.29HV0.3。涂层的摩擦系数和磨损率均随着温度的升高而降低,800℃时Cr3C2/NiCr-CaF2和Cr3C2/NiCr-Ag-MoO3-CaF2涂层的摩擦系数和磨损率最低,最低摩擦系数分别为0.30和0.19,最低磨损率分别为3.84×10^-5、2.89×10^-5mm^3/(N·m)。结论CaF2可以改善600℃以上的摩擦学性能,Ag、CaF2、MoO3在涂层磨损表面发生摩擦化学反应生成的钼酸银和钼酸钙,可以有效地改善Cr3C2/NiCr涂层在600℃以上的摩擦学性能。The work aims to investigate and study the friction behavior and wear mechanisms of Cr3C2/NiCr-Ag-MoO3-CaF2 and Cr3C2/NiCr-CaF2 cermet coatings sliding against ZrO2 ceramic ball at room temperature of 800 ℃. Cr3C2/NiCr cermet coatings containing CaF2, Ag and MoO3 were prepared on the surface of Inconel 718 steel by atmospheric plasma spraying technology with Cr3C2/NiCr as substrate materials and CaF2, Ag and MoO3 as solid lubricants. Friction and wear behavior of cermet coatings were studied by UMT-3 high temperature friction and wear tester at room temperature to 800 ℃. The micro-hardness and bond strength of the coating were tested by micro-hardness tester and universal material testing machine. The microstructure, phase composition and microscopic morphology of the wear track of the cermet coating were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Raman spectroscopy. The Cr3C2/NiCr-CaF2 and Cr3C2/NiCr-Ag-MoO3-CaF2 cermet coatings had dense microstructure, the micro-hardness and bonding strength of cermet coatings decreased with the increase of solid lubricant content and the bonding strength and micro-hardness of cermet coating was 46.45 MPa and 524.61HV0.3, 36.65 MPa and 478.29HV0.3, respectively. The friction coefficient and wear rate of the cermet coatings decreased with the increase of temperature and reached the lowest at 800 ℃, 0.30 and 0.19, 3.84×10^-5 mm^3/(N·m) and 2.89×10^-5 mm^3/(N·m), respectively. CaF2 can obviously improve the tribological performances of Cr3C2/NiCr cermet coating above 600 ℃. The improved the triboloical properties of Cr3C2/NiCr cermet coatings above 600 ℃ are mainly attributed to the synergistic lubricating effect of molybdates formed on the worn track by tribo-chemical reaction of Ag, CaF2 and MoO3.

关 键 词：大气等离子喷涂 Cr3C2/NiCr金属陶瓷涂层 摩擦化学反应 润滑涂层 高温涂层 摩擦学行为 

分 类 号：TH117[机械工程—机械设计及理论]